This invention relates to improved apparatus for wiring through a wall of a sealed enclosure, and more specifically to the use of a printed circuit board as the conducting element through said wall as an improvement over the standard bulkhead connectors now in common use. Standard printed circuit connectors are mounted and soldered onto the etched circuit board and cable connections may be then made to the connectors by wiring the cable conductors to blank circuit boards which are inserted into the connectors. Circuit boards containing electronic components may be mounted directly into the printed circuit connectors thereby minimizing the number of cables required.
A recurring problem in the electrical industry is the requirement to make numerous electrical connections to a piece of equipment that must operate in a sealed enclosure. An example of such equipment in the data processing field is a disc drive system wherein the discs themselves must be sheltered from abrasive contaminants which would cause wear between the recording heads and the recording surface, thereby appreciably shortening the useful life of the discs and heads. Therefore, the discs are kept inside a pressurized enclosure wherein a stream of filtered air is constantly blown over the surfaces of the discs.
Concurrently, a large number of connections must be made to the recording heads. This problem is particularly bothersome in a head-per-track system where a large number of wires are necessary. In the typical installation, a double ended bulkhead connector is used. In the case where a large number of wires are necessary an excessively large bulkhead connector or a number of bulkhead connectors are required. Standard cable connectors are expensive, the electrical characteristics of each line in a connector is unpredictable since the impedance characteristics are dependent upon the location of the wire in the bundle, the fabrication costs are high since the wiring of a connector must be done by hand, and wiring errors in the assembly of connectors are common.